I was at nGenera’s annual Fall All Member’s meeting this week in Memphis and ran across Microsoft’s Jerry Carlson at Day One’s closing reception. As we stood within inches of the biggest pile of Brie I’ve ever seen and a table full of crackers, Jerry showed me and my iPhone-loving colleagues a cool little app they have in the app store.

It’s called Microsoft Tag and here’s how it works. Step 1 involves going to the iPhone AppStore and searching for Microsoft Tag (a free app) and installing it on your phone. It only takes a few seconds, even in the middle of an historic downtown hotel in Memphis (The Peabody) where the walls are thick and the brie is thicker.

Step 2 involves taking a photo using the Microsoft Tag iPhone app – in this case, a photo of Jerry’s business card. As you can see in the pictures, Jerry carries a special version of his around with him that is laminated. Side 1 is the typical name, address, phone, etc., which is basically irrelevant for the purpose of this exercise. Side 2 is the photo tag, which is the important part.

What you do is aim your iPhone close enough to the photo image on the card to get a reasonable amount of light and clarity. Then you touch the photo button, just like on the iPhone native camera and, voila, the screen on your iPhone app indicates to you that the image was successfully captured by displaying a little green box around it.

If the image capture fails, a little red box appears around the image and you simply retake the shot. Since we were in a modestly dimmed reception hall, it was after hours, and the enormous container of brie was causing a shadow effect, it took the third try for to get the green box.

But, once you have the green box, Step 3 involves pressing the little button that appears at the bottom of the iPhone Tag app, which asks “Use.” The, next thing you know, up pops Jerry’s contact info in an iPhone contact record, ready to be merged into an existing contact record or be created as a new one in my database. Pretty cool.

After Jerry in rapid succession talked four of us in a row into loading the app, we all chatted for a few moments more about the practical implications of such a technology. Jerry said there is a lot of experimentation going on presently to see where this fits in the universe of other item identification options, which obviously range from barcodes to RFID to Bluetooth.

We had a brie-f chat about some of the future scenarios of federated identity management models and then it was off to dinner on Beale Street, the Memphis mash of Chicago’s Rush Street and Austin’s 6th Street – neon and barbeque.